ZyXEL Communications ZyXEL ZyWALL P1, User Manual

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ZyWALL P1 User’s Guide
Chapter 14 UPnP 215
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H A P T E R
14
UPnP
This chapter introduces the Universal Plug and Play feature.
14.1 Universal Plug and Play Overview
Universal Plug and Play (UPnP) is a distributed, open networking standard that uses TCP/IP
for simple peer-to-peer network connectivity between devices. A UPnP device can
dynamically join a network, obtain an IP address, convey its capabilities and learn about other
devices on the network. In turn, a device can leave a network smoothly and automatically
when it is no longer in use.
14.1.1 How Do I Know If I'm Using UPnP?
UPnP hardware is identified as an icon in the Network Connections folder (Windows XP).
Each UPnP compatible device installed on your network will appear as a separate icon.
Selecting the icon of a UPnP device will allow you to access the information and properties of
that device.
14.1.2 NAT Traversal
UPnP NAT traversal automates the process of allowing an application to operate through
NAT. UPnP network devices can automatically configure network addressing, announce their
presence in the network to other UPnP devices and enable exchange of simple product and
service descriptions. NAT traversal allows the following:
• Dynamic port mapping
• Learning public IP addresses
• Assigning lease times to mappings
Windows Messenger is an example of an application that supports NAT traversal and UPnP.
See Chapter 11 on page 177 for further information about NAT.
14.1.3 Cautions with UPnP
The automated nature of NAT traversal applications in establishing their own services and
opening firewall ports may present network security issues. Network information and
configuration may also be obtained and modified by users in some network environments.